The present invention relates in general to a numeric display of the multiple-segment type. More particularly, this invention relates to a segment display preferably comprising seven or fewer segments for displaying numerals of the Arabian writing.
In the Near and Middle Eastern countries, such as in Iran, Pakistan and the Arab countries, a different numbering system which shall be referred to herein as the Arabian writing system, is used, as disclosed hereinafter, than the conventional numbering system used in the Western countries. In the West, numbers are displayed in Western "arabic" numerals. The display usually used to display the "arabic" numerals is a seven-segment display that is digitally controlled, usually by means of a binary code. Some consideration has been given to the display of numbers commonly used in the Arab countries. See, for example, U.S. Pat. No. 3,968,583 to Allam which discloses a twelve-segment display with all twelve segments being used in one combination or another for displaying all Arabian numerals. One disadvantage of this twelve-segment display is that the display is rather complex and requires the use of segments of narrowly restricted shape. Moreover, the twelve-segment display is not easily, if at all, adaptable for use with existing drive circuitry now used with "arabic" numerals. In general the drive circuitry used to display "arabic" numerals is for driving seven segments and thus in order to drive twelve segments a totally new circuit format is required, which would employ many more electrical leads or equivalent mechanical devices. Furthermore, the drive circuitry for the twelve segments is considerably more complex logically than for the seven-segment display. In circuit designs that employ time multiplexed addressing and/or energizing of segments, the seven-segment display has much simpler control electrical waveforms in the circuitry for their generations, than a display employing more than seven segments for a numeral.
Accordingly, it is an object of the present invention to provide a seven-segment display, and a display having fewer than seven segments for the display of all Arabian writing numerals, as distinguished from "arabic" numerals. The reduction of number of segments allows a reduction in the number of leads and simplification of the driving circuitry.
Another object of the present invention is to provide a display for Arabian writing numerals which will enable those familiar with that numeric system to read such devices as electronic watches, clocks, calculators, digital thermometers, computers, radios and any other instruments with numeric displays. The present invention is compatible with many segment display mechanisms including liquid crystal displays, light emitting diode displays, and vacuum fluorescent displays, for example.
A further object of the present invention is to provide a display for Arabian writing numerals wherein the display can be compatible with the hardware employed to drive displays for western "arabic" numerals employing seven segments. This compatibility is significant in that then like drive circuitry may be used for displaying either "arabic" numerals or Arabian writing numerals.
To accomplish the foregoing and other objects of this invention there is provided a multiple segment display for displaying numerals of Arabian writing. This display has a maximum of seven segments so as to be compatible with existing hardware drive circuitry now used for seven-segment displays of "arabic" numerals more commonly used in the Western countries. There is disclosed herein a number of different embodiments showing a variety of formats for these Arabian writing seven-segment displays. In the drawings disclosed hereinafter, these different formats are separated into seven basic groups. The majority of these groups contain seven segments for their basic arrangement but some groups can display all numerals with the use of only six segments. In accordance with the present invention the seven segment Arabian writing display is accomplished to a great extent by making common usage of some segments for deriving different numerals. For example, in the prior art, such as in the Allam patent totally different segments are used for the numerals five and eight, whereas in accordance with the present invention two segments in common, are used in deriving these two numerals in accordance with one format of the present invention.
Another important feature of the present invention is that the numerals in each format are displayed in substantially the same position while in the prior art such as in the Allam patent where as many as twelve segments are used, different numerals shift positions when displayed. For example, the numeral five is displayed at the right side of the display in the Allam patent, while the numeral eight is displayed at the left side of the display. Thus, the prior art construction does not at all lend itself to multiple numeral displays wherein it is important that the spacing between numerals remains substantially constant. Also another advantage of the invention is that multi-digit numbers can now be displayed more compactly which is important for such displays as calculator displays.